Here's a related statement from an Acer spokeswoman:
"We will release any required BIOS updates and/or drivers for any systems on the approved list. If a product is not on the approved list, a customer may still be able to install Windows 10, but we will not release new BIOS/drivers for Windows 10, cannot guarantee it will work, etc."
The other PC makers I reached out to shared similar sentiments.
Microsoft, PC makers cagey on Windows 10 support for older systems
Microsoft provides tools that are designed to help. If you have a white "get Windows 10" logo in your system tray, chances are your PC will run Windows 10. If you don't, you can visit Microsoft's "The 'Get Windows 10' app doesn't appear in Windows 7 or 8.1" support page and follow the instructions. But the process is way too confusing.
I ran the troubleshooting tool referenced on the page, and it said my system isn't Windows 10 capable. But when I drilled down into the test, it turned out that I hadn't installed some recent Windows 7 updates, and without them I couldn't download the app needed to reserve a copy of Windows 10.
It took me close to an hour (and two or three reboots) to download a bunch of updates, and then the application said my system can run Windows 10. But then, another complication: My Lenovo laptop is not listed as a supported system by the manufacturer.
I contacted Lenovo, and the company said it thought the system would run Windows 10 ... but couldn't guarantee it. Then it suggested calling Microsoft if I have a problem. O-K. So, the official take from my PC's maker: Maybe your trusty laptop will play nicely with Windows 10 — but maybe it won’t.
A Windows 10 upgrade is supposed to stop itself and warn users that it can't complete the job because the system isn't compatible, but the consequences of stopping in the middle of an upgrade aren't at all clear. That said, Windows 10 is getting a lot of news coverage, and I haven't heard about many problems with upgrading to newer systems. (I have, however, seen quite a few complaints about the mysterious way Microsoft is handling its upgrade and patch processes.)
My advice: If your system isn't listed on the manufacturer's support page, don't even try to upgrade. Unless you purchased an extended support package, your system is likely out of warranty, and the maker may not be willing to help you out if something goes awry — and neither will Microsoft.
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